Acta Chimica Slovaca
·
2021
·Vol. 14
·期 1
·60-65
·
IF 0
Laura Jánovová,Katarína Hroboňová
Lactic acid is a biologically important organic acid existing in two enantiomeric forms which are differently metabolized in the human body. In this paper, direct chiral separation of lactic acid by high performance liquid chromatography is presented. Five chiral stationary phases based on macrocyclic antibiotics were used for enantioseparation and chromatographic parameters, such as retention factors, resolution and selectivity factors, were determined under different column temperatures ranging from 5 to 45 °C. Optical isomers of lactic acid were efficiently separated using chiral stationary phases based on teicoplanin (RS = 1.9
) and ristocetin (RS = 1.7
) in reversed-phase separation mode at the column temperature of 25 °C.
研究领域:
分析化学
·
生物化学
✓ 已验证
DOI
MICROCHIMICA ACTA
·
2019
·Vol. 187
·期 1
·1-8
·
IF 5.479
Xi Ying,Du Yingxiang,Sun Xiaodong,Zhao Shiyuan,Feng Zijie,Chen Cheng,Ding Wen
A monolithic capillary column was prepared by single-step copolymerization of the ionic liquid 1-vinyl-3-octylimidazolium bromide (VOI) and styrene. The VOI and styrene monomers were introduced to provide multiple interaction sites and increase hydrophobicity and aromaticity of the monolithic column, respectively. The effect of porogen ratio, monomer ratio and reaction temperature on permeability was investigated. The resulting column was characterized by scanning electron microscopy, and the results suggest that the column possesses high porosity and good homogeneity. A relatively strong anodic electroosmotic flow was generated over a wide range of pH values (pH 2.0–10.0), and this facilitates the rapid separation of analytes within 12 min. Alkylbenzenes, polycyclic aromatic hydrocarbons (PAHs), proteins and amino acids were used to evaluate the performance of the monolithic column under capillary electrochromatography mode by UV detection. Mixed-mode retention mechanisms including hydrophobic interaction, π-stacking, ion-exclusion interaction were observed. The monolithic column exhibits high column efficiency (8.72 × 10 4 plates∙m −1 ) and satisfying separation capability (the resolution of four alkylbenzenes: 2.54, 2.86 and 4.62, four PAHs: 2.79, 4.83 and 4.77, three proteins: 4.35 and 2.86, two amino acids: 3.34).
Schematic representation of capillary electrochromatography (CEC) systems with ionic liquid and styrene based organic polymer monolithic column for separation of alkylbenzenes, polycyclic aromatic hydrocarbons, proteins and amino acids.
研究领域:
分析化学
·
电化学
·
色谱学
·
高分子科学
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Xin-Yi Sui,Bing-Qi Zhu,Yue Li,Huan-Jie Che,Jing Li,Jingbin Zeng,Jian-Bo Qu
A bimodal gigaporous anion-exchange medium with the ion-exchange capacity of 0.215 mmol/ml was successfully developed based on hydrophilic gigaporous polystyrene (HGPS) microspheres (diameter between 60 and 115 μm). There are two types of pore in the medium, i.e., gigapores (0.3–7 μm) and mesopores (10–60 nm). The presence of gigapores in the medium can induce convective flow of mobile phase within microspheres, therefore contributing to high column permeability (3.55×10 −10 m 2 ), high dynamic adsorption capacity and high protein resolution at high flow velocities. The mixture of hemoglobin, transferrin and ovalbumin can be baseline separated within 3 min at 2529 cm/h. All the results indicate that anion-exchange medium as developed is very promising for large scale high-speed protein chromatography.
研究领域:
化学工程
·
生物化学
·
分离科学
·
高分子化学
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产品关联
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 11
·2201
·
IF 4.967
Qi Xu,Jianwei Lin,Guichang Jiang
At present, the consumption of polyurethane is huge in various industries. As a result, it has become a research hotspot to use environmentally friendly and renewable bio-based raw materials (instead of petroleum-based raw materials) to prepare polyurethane. In this paper, epoxy soybean oil (ESO) was used as raw material, and polyethylene glycol (PEG-600) was used for ring opening. Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) analysis proved that soybean oil-based polyester polyols was prepared. Soybean oil-based polyurethane (SPU) was synthesized by the reaction of the soybean oil-based polyol with isophorone diisocyanate (IPDI), so as to save energy and protect the environment. The properties of SPU films were adjusted by changing the R value (the molar ration of -NCO/-OH) and the film forming temperature. The chemical structure and properties of the SPU were characterized by FTIR,1H NMR, gel permeation chromatography (GPC), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results show that the mechanical strength, water contact angle, microphase separation degree, barrier property, and thermal stability of SPU films gradually increase, while the transparency, oxygen permeability coefficient and moisture permeability coefficient of SPU films gradually decrease with the increase of R value and film forming temperature.Keywords:epoxy soybean oil;soybean oil-based polyurethane;polyethylene glycol
研究领域:
材料科学
·
高分子化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）